This is the Key used to store and access individual values in Accumulo. A Key is a tuple composed
of a row, column family, column qualifier, column visibility, timestamp, and delete marker.
Keys are comparable and therefore have a sorted order defined by compareTo(Key).

set

Sets this key's row, column family, column qualifier, column visibility, timestamp, and delete
marker to be the same as another key's. This method does not copy data from the other key, but
only references to it.

compareTo

Compares elements of a key given by a PartialKey. The corresponding elements (row,
column family, column qualifier, column visibility, timestamp, and delete marker) are compared
in order until unequal elements are found. The row, column family, column qualifier, and column
visibility are compared lexicographically and sorted ascending. The timestamps are compared
numerically and sorted descending so that the most recent data comes first. Lastly, a delete
marker of true sorts before a delete marker of false. The result of the first unequal
comparison is returned.
For example, for PartialKey.ROW_COLFAM, this method compares just the row and column
family. If the row IDs are not equal, return the result of the row comparison; otherwise,
returns the result of the column family comparison.

appendPrintableString

Appends ASCII printable characters to a string, based on the given byte array, treating the
bytes as ASCII characters. If a byte can be converted to a ASCII printable character it is
appended as is; otherwise, it is appended as a character code, e.g., %05; for byte value 5. If
len > maxlen, the string includes a "TRUNCATED" note at the end.